Rare earth extraction apparatus and method of use thereof

Abstract

The invention comprises an apparatus and method of use thereof for generating a rare earth from a rare earth oxide, comprising the steps of: (1) dissociating the rare earth oxide and hydrogen gas in a reaction chamber by inductively heating the reaction chamber to greater than 2000° K to form the associated rare earth and water vapor in a reaction process; (2) driving the reaction process forward by removing the water vapor from the reaction chamber by condensing and freezing the water vapor on a first cold trap surface as water ice, where the reaction comprises: RE 2 O 3 +3H 2 →2RE+3H 2 O, where REO is a rare earth oxide and RE comprises a rare earth in the rare earth oxide; and/or (3) monitoring the reaction process by monitoring generation of at least one of the rare earth and the water in a control system designed for continuous/semi-continuous operation.

The invention claimed is: 
     
         1 . A method for generating a rare earth from a rare earth oxide, comprising the steps of:
 dissociating the rare earth oxide and hydrogen gas in a reaction chamber by inductively heating the reaction chamber to greater than 2000 K to form the rare earth and water vapor in a reaction process;   driving the reaction process forward by removing the water vapor from the reaction chamber by condensing and freezing the water vapor on a first cold trap surface as water ice, according to Le Chatelier's principle;   prior to said step of dissociating, placing the rare earth oxide as a powder into said reaction chamber and cooling said reaction chamber to lower than −25° C.; and   after said step of placing and prior to said step of dissociating, reducing pressure of said reaction chamber to less than 0.05 torr, wherein a water impurity of said rare earth oxide boils off as less than 1 torr at a molecular velocity leaving greater than ninety percent of said rare earth oxide in said reaction chamber.   
     
     
         2 . The method of  claim 1 , said reaction process comprising: 
       
         
           
             
               
                 
                   R 
                   ⁢ 
                   
                     E 
                     2 
                   
                   ⁢ 
                   
                     O 
                     3 
                   
                 
                 + 
                 
                   3 
                   ⁢ 
                   
                     H 
                     2 
                   
                 
               
               → 
               
                 
                   2 
                   ⁢ 
                   R 
                   ⁢ 
                   E 
                 
                 + 
                 
                   3 
                   ⁢ 
                   
                     H 
                     2 
                   
                   ⁢ 
                   O 
                 
               
             
           
         
         where REO is a rare earth oxide and RE comprises a rare earth in the rare earth oxide, where the rare earth comprises at least one of: cerium (Ce), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), holmium (Ho), lanthanum (La), lutetium (Lu), neodymium (Nd), praseodymium (Pr), promethium (Pm), samarium (Sm), scandium (Sc), terbium (Tb), thulium (Tm), ytterbium (Yb), and yttrium (Y). 
       
     
     
         3 . The method of  claim 1 , further comprising the steps of:
 weighing the cold trap to determine mass of water ice by difference;   calculating mass of hydrogen in the water ice; and   a controller system, provided said mass of hydrogen, injecting hydrogen gas into said reaction chamber to replace a portion of said mass of hydrogen while maintaining hydrogen concentration in said reaction chamber at less than four percent hydrogen gas by volume.   
     
     
         4 . The method of  claim 3 , further comprising the steps of:
 calculating a reduced mass of the rare earth oxide in said reaction chamber using stoichiometry and the mass of hydrogen;   said controller system using a solid feed system to mechanically deliver additional rare earth oxide to said reaction chamber to replace at least a portion of the reduced mass of the rare earth oxide.   
     
     
         5 . The method of  claim 1 , further comprising the step of:
 collecting the rare earth product in at least one of a liquid form and a solid form after settling to the bottom of the reaction chamber as a result of a density difference of the rare earth product from the rare earth oxide dissociation particles in a plasma in the reaction chamber.   
     
     
         6 . The method of  claim 5 , further comprising the step of:
 weighing said collected rare earth product to determine a product mass of said rare earth.   
     
     
         7 . The method of  claim 6 , further comprising the step of:
 a controller system, using said product mass of said rare earth and stoichiometry, mechanically delivering additional rare earth oxide to said reaction chamber to replace at least a portion of said rare earth oxide calculated as being converted to said rare earth product.   
     
     
         8 . The method of  claim 6 , further comprising the steps of:
 a controller system, using said product mass of said rare earth and stoichiometry to calculate a mass of hydrogen gas consumed in the reaction process; and   said controller system injecting additional hydrogen gas into said reaction chamber to replace at least a portion of the mass of hydrogen gas consumed in the reaction process while maintaining a hydrogen gas concentration of less than four percent by volume in said reaction chamber.   
     
     
         9 . The method of  claim 1 , further comprising the step of:
 a controller system redirecting the water vapor from said first cold trap to a second cold trap through control of an exit valve; and   regenerating said first cold trap while said second cold trap said step of drives the reaction process forward by condensing and freezing the water vapor.